1. Field of the Invention
The present invention relates to an acid-resistant endoglucanase and its use.
2. Description of the Related Art
In recent years, biomass created by the photosynthetic action of plants has shown increasing promise as an alternative to finite petroleum resources. A range of endeavors to utilize biomass in energy and the production of various types of materials is in progress. In order for biomass to be effectively utilized as an energy source as well as a raw material for other applications, it is essential that the biomass be rendered by saccharification into a carbon source which is available for uses by animals and microorganisms.
To utilize cellulose, a typical component of biomass, it is regarded as desirable to convert cellulase to glucose (i.e. saccharification) by decomposing the cellulose with a cellulase such as endoglucanase. Various cellulases and modified cellulases capable of efficiently decomposing cellulose are being tested for this purpose. In particular, a number of investigations have been conducted on endoglucanases produced by filamentous fungi of e.g., the genus Trichoderma (Patent Document 1, 2 and 3). In addition, a process of inducing the display of cellulase at the surface of yeast cells, decomposing cellulose to glucose with the cellulase, and using the resulting glucose as a carbon source to produce ethanol is also being studied (Patent Document 4).
Prior Art Documents
(Patent Documents)
Patent Document 1: U.S. Pat. No. 7,094,588 B2
Patent Document 2: U.S. Pat. No. 6,268,328 B1
Patent Document 3: U.S. Pat. No. 6,623,949 B1
Patent Document 4: International Disclosure WO 01/079483